Bobbin



Aug. 4, 1936.

C. K. DUNLAP BOBBIN Filed June 12, 1935 Patented Aug. 4, 1936 PTENT OFFICE BOBBIN "Charles` K. Dunlap, Hartviue; s. o., assignor to Sonoco' Products Company,.Hartsvirl le, S. C., a

i w .'corporation fof South Carolina o Application Janem, 1985, serial No. '26,263

' 1 olaim. (c1. 242-122) .The present invention relatesqtobobbins and particularly to .the simple, light type of bobbin adapted for use as a core fora package of thread cr yarn in the textile industry.` o

Many types of bobbins have heretofore` been suggested and are now used in-'large quantities in the textile industry. One type. which has met With widespread favor comprisies a cylindrical barreltand a frusto conical base, .thevbarrel and base being coaxally dsposed: a'nd. one.` end of the barrel being housed and retained within the base, the other end of the'barrel having no head or base thereon.

In forming a thread package upon such a' bobbin it is first placed upon the winding mandrel of a winding machine and, while the mandrel and the superimposed bobbin revolve about the axis of the mandrel, a thread package is built up thereon by the action of a thread feeding and traversing mechanism, this mechanism having a thread guide which moves in a closed path parallel to the axis of the winding mandrel and from which guide the thread passes directly upon the bobbin. The winding mandrel and the traversing mechanism just described comprise portions of thesame winding machine and are definitely positioned or located with respect to each other. It is intended that the mandrel and traversing mechanism occupy such relative position that the initial thread winding upon the bobbin is begun exactly at the junction of the conical and cylindrical thread receiving surfaces of the bobbin.

If, for any reason, the bobbin is not properly o placed upon the winding mandrel, or is not so constructed that the junction of the cylindrical and frusto conical thread receiving surfaces occupy the desired relationship .to the thread feeding and traversing mechanism, the initial layers of the thread Winding will be imperfectly placed.

Manufacturers vof bobbins have naturally made every attempt heretofore to secure uniformity and accuracy of dimension in their products but, in the manufacture of inexpensive bobbins in large numbers, a certain proportion of bobbins are made which do not seat upon the winding mandrel with the desired degree of accuracy. This is particularly true where paper is employed in the manufacture of the bobbin and where the annular end of the barrel itself is employed as an abutment surface adapted to contact with the seating surface formed on the winding mandrel when the bobbin is placed in position on such a mandrel. Thus, in a series of such bobbins, the distances between the ends of the respective barrels and the lines of junction between the conica] and cylindrical surfaces may vary considerably, insome of the bobbins this distance being eXactly that desired and in others being greater or less than that desired. o

The present invention contemplates the provision of Va bobbin which, while yet inexpensive to produce, light in weight and durable, is formed in such a-manner that the distance between the surface thereof which is adapted to contact with an abutment surface vof the mandrel Sand therefore definitely locate or position the bobbin' upon the mandrel, is in every case the same distance from the line of junction between the cylindrical `and frusto conical thread receiving surfaces of the bobbin. When placed on the winding machine, therefore, each and every bobbin of the series will be definitely and accurately located with respect to the thread feeding or traversing mechanism and hence inaccurate and faulty windng 20 is eliminated. Generally speaking the invention consists in the combination of a cylindrical bar- 5 rel and a one piece base formed for instance of bakelite, hard rubber, or any other similar material which, after having been formed into a bobbin base, will maintain its shape and its original dimensions While at the same time is comparatively inexpensive and durable.

In the accompanying drawing one embodiment Vof the invention is disclosed by way of example and will be hereinafter described in detail.

In the drawing:

VFigure 1 is a side elevation of the improved bobbin;

Figure 2 is a longitudinal section through the same, portions of a winding mandrel being indicated in chain lines;

Figure 3 is a bottom plan view of the bobbin showing details of the base thereof.

The barrel of the bobbin is indicated at IO and the base `at Il, the barrel comprising a cylindrical paper tube, .preferably formed by winding a sheet of paper convolutely upon a cylindrical mandrel and gluing or pasting the several convolutions together, and the base being preferably formed of bakelite, hard rubber,V or other such plastic substance by a molding operation, after which the substance is allowed to harden, or is subjected to some hardening treatment.

It will be perceived that the base has a frusto conical portion which is indicated at |2 and an axial cylindrical portion |3 integral therewith. The cylindrical portion |3 is axially and cylindrically apertured to receive the end of the paper barrel |O and at its outer end this inner barrel receiving cylindrical aperture has a, short section of enlarged diameter, indicated at Ill, which receives the expanded end |5 of the barrel IO. Within the end of the barrel is a metallic retaining ring IB which prevents contraction of the expanded barrel and thereby looking the barrel endvwithin the base against relativaaxal movement in: oneLdire'CtiOn. Iti maybelifurther retained by a suitable adhesive or other looking means if found necessary or desirable. The annular lower end surface of the cylindric'al portion or skirt |3 of the base is disposed ima plane transverse to' the axis `of the4 bobbin and is adapted to seat upon Itheshoulderoor;collar l'l which forms a part of the winding mandrel |8. The circular line of junction of the thread receiving surfaces of base and"^barre1=-fis-indicated at 19 in Figure 1 and by reasonofthe fact that the base Lis formed in,one piece and of 'dur'ab'le materiaL'j *it is obvious `4that' 'the distance indicated .a.t..'A' in jEigure 2; between the annulan lower; edgesurface of part; ;|`3 ..and w .the line of junction 'l 9,,..wi 11,alwaysbeithefisame for a11..bobbins .of a..series employing `bases-sueh a's illustrated. Enea. ,endrof Vthe ,paper barre1:lO does-inotxtouch the. :collar l lf-of; thezwinding` mandrel =but.-theposition ofthe -bobbin 1 uponlfthe mandrel ;';fis :wholly .rzdctermined :byl contact betw eenjzthe base-''-lizancif.the` collar.

:The obasezitzself 'fmay 1.;be.: formedz'zinzvarious ways and of various materials but that illustrated in the drawing is eminently satisfactory. Strengthening webs 2O are shown in Figures 2 and 3, these strengthening webs being disposed laterally of the bobbin and connecting the outer 5 cylindrical surface of part |3 to the inner conical wall of part |2. In all instances these strengtheningwebs arenot ,necessary,.but in certain instancesithey may 'be increased in number as, Where it is desired to make the parts 12 and |3 as light as possible and yet have a base which is rigid and durable. Having thus described the invention, what is claimed as new andidesired to be secured by flLettersPatentfis:

Az-bobbin-radapted to serve as a core for a thread package comprising a cylindrical paper 'barrelf"and=a-onepiece base, said base having ``.a centralthollow cylindrical portion, and a conical skirt portion, said portions having their 20 :inner e'nds;joineditogetherzand'` ith'eir 'outer ends spaeed apazrtfradiaily;disposedfibracing .'webs vinteg-ml: with:;thessaidztwo-basezzportions; .theend of the barrel being'fhrozused;xeritirelyI within'the .hollowzeylindrieab'oentrahportion andfthefend of 25 thisnportionmprojeoting outwardly 'beyond the barrelefendaanditerminatingrzinztan :Vannularrend smifacedisposedz'zirriaeplane normalwrtonthe `.axis oftithe'ibobbina andixcomprisingt a seatingssurfaice adaptcdfsto=1tests upon-:ithe co1'1ar;.'of a winding" 30 mancl'rel;

:LIGHARLES KaDUNLAP. 

